Mining-bit.



Wsw. 1 El G. BITTENBENDER.

` MINING BIfI. l Prmonlox FILED 11116.29, 1910.

ratenteaqan, 10,1911.

MINING-BIT.

Specification of Letters Patent.

Patented Jan. 10.. 1911.

. Application led August 29, 1910. Serial No. 579,404.

To all whom it may concern:

Beit known that we, WILLIAM W. BITTEN- BENDnR and ELIAS Gr.BITrnNBENDnR, both citizens of the United States, residing at Nanticoke,county of Luzerne, State of Penn'- sylvania, have invented certain newand u seful Improvements in Mining-Bits, of which the following is aspecification, reference being had therein to the accompanying drawglhisinvention has relat-ion to that class of drills or bits that areemployed in 'mining coal or in-quarrying rock and any other analogouspursuits and, among the obJects of the invention `is the provision of abit which shall be effective in operation, simple.

and inexpensive. in structure, easily sharpcned, strong and serviceableand adapted to be used in connection .with a hand or power operatedapparatus.

Other and-further objects of the invention will appear in the followingdescription of' the invention and the novel features thereof will bepointed out yin the appended claims.

Referring to the drawings-Fignre 1 is a side elevation of a bit constrcted in accordance with our invention; ,ig 2 is an edge View; Fig. 3 isa cross section online 3-3 of Fig. 1; and Fig. t is a diagrammatic planillustrating the manner of producing blanks of the bit' from suitablematerial in sheet form.

Like numerals of reference refer to like parts in the several figures ofthe drawing. I

A represents the tang or shank of the bit which is, as shown, polygonalin cross section, thereby adapting it to be grasped and. operativelyheld bv the chuck of any drilling machine or by the well known bit-braceemployed by miners when operating bits by hand power.

B represents the blade portion of the bit from which project thedrilling points C, C, C and Cv. The blade portion B hasupon either sidethereof a Astrengthening rib B which merges into the shank A atdiametrically opposite corners thereof, the shank being, ashereinafterdescribed, swaged to a greater thickness than the blade portion B of thebit. The drilling points of the bit are tapered in pairs with theytapers of each pair arranged reversely to those of the other pan'. Asshownin Fig. 1, the pair .at thelett is tapered toward the observer, asshown at c and of, while the opposite air is tapered in the oppositedirection as s own by dotted lines 1n said figure. The reverse taperingis also clearly shown in Fig. 3. In like manner, the extreme ends of thedrilling points are tapered in opposite directions as shown at ci', c2,Fig. 1, in one direction,

and in the other direction by dotted lines in said figure, at c3, c3.

By the construction above described, we provide a bit which can beemployed either in a drilling machine or which may be operated by handpower and which is inex-v pensive and obtainable by the individual minerat slight cost and which, by reason of the extension of tle centraldrilling points beyond those of the outer points of the bit, renders theoperation of the drilling less laborious, the cutting edges, produced bythe beveled ends c2, c3, in opposite directions, first enter the coal,and act to center the bit as a whole, so that when the shorter pointscontact with the coal, the longer points not only act as cutters but asguides to secure the proper alinement of the work being done. llVhen thefull depth of the drilling points are within the coal or other material,the

end s of the slots between the drilling points, which ends are beveledas shown at c4, corresponding to the beveling of the' drilling points,begin to act upon-the central, cylindrlcal and outer annular cores,which have been formed by the operation of the drilling .points up tothis time and gradually and at the same rate of cutting that is done bythe points themselves cut away and remove said Icores, the materialremoved passing readily Iover thev blade portion of the bit.

While we do not limit ourselves to any par- Itlicular method ofmanufacturing our bit, it

is observed that `the formation thereof adapts it readily to bemanufactured from sheet steel with4 slight waste. Steel of the properthickness to form the drilling points of the bit, and in sheet form, maybe em-1G' ployed and blanks cut therefrom in inter laced relation toeach other, whereby small portions X Fig. 4 would constitute the onlwaste material in the blade of the bit. In

this method of manufacture, the portion of the blank which is to formthe tang or shank A of the bit, is cut wider than the completed .tangand is subsequently pressed or swaged by dies to form the polygonal tangof greater thickness than the blade portion of the bit. L 11 Havingdescribed our invention and set forth its merits, what We Claim anddesire to i secure by Letters Patent is l. A biteoinprising a shank7 ablade por- 1y `tion and drilling' points arranged 1n pairs parallel Witheach other and beveled in op# posite directions the bevels of thecentral pair being oppositely disposed and merging at a point midway oftheir adjacent Cutting edges the central pair being longer than theadjacent outer drilling points.

2. A bit comprising a shank', a blade portion and a series of paralleldrill points projected therefrom in a common plane the eenl tral pairbeing arranged each one at one side f of the center of the bladeportion, beveled in i opposite directions, the bevel of one merging intothe bevel of the other midway between their adjacent eiittiiig edges thelatter beiiig

